The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 17, 1992
Filed:
Oct. 11, 1990
G Graham Allan, Seattle, WA (US);
The Board of Regents of the University of Washington, Seattle, WA (US);
Abstract
There is also disclosed a process for the production of filled paper using never-dried pulp fibers and filler comprising an insoluble precipitate that is precipitated in situ within the cell wall of the fibers. The process first immerses the never-dried pulp fibers in a first solution containing a soluble salt or salts, filters the pulp fibers from the first solution, and reimmerses the never-dried pulp fibers containing the first solution in the pores into a second solution, wherein the second solution comprises soluble salt or salts different from those of the first solution and able to form an insoluble precipitate with the salt or salts of the first solution. The filled, never-dried pulp fibers are filtered and washed and either used to form filled paper products or dried to filled pulp fibers for later use in papermaking.